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Simple SummaryThis project monitored the internal micro-environments of live poultry transport trailers during loading and transport. For the 28 trips evaluated, trailers were modified using common USA industry mitigation practices designed to optimize bird comfort under a wide range of environmental conditions. In the cold season, double boarding of the exterior area of the transport modules elevated the internal temperature more than 8 °C above ambient temperatures as low as −16 °C. However, the temperature elevation may not be sufficient when ambient temperature was below 0 °C. In the warm season, surface wetting of birds and evaporative cooling applied during on-farm loading maintained trailer thermal conditions at or below ambient temperature for part of the road transport. However, this study suggests that additional improvement in equipment design or management is warranted when temperatures are extremely cold or hot.AbstractThis observational study was conducted to characterize the thermal micro- climate that broilers experienced in commercial poultry transporters under various weather conditions and typical management practices in the South Central USA. We continuously monitored temperature and relative humidity in 45 interior locations of 28 fully-loaded commercial trailers over 2 year spans from 2015–2016 in South Central USA. In the cold season, double boarding of the exterior area of the transport modules maintained temperatures at least 8 °C warmer than ambient temperatures as low as −16 °C. Overall, temperature at all locations decreased as transporters traveled from farms to processing plants during winter trips with double boards. In the hot season, assistance by evaporative cooling during on-farm loading resulted in interior temperatures within ± 2 °C of ambient conditions (up to 36 °C) during road transport. In the summer months, trailers uniformly gained 2 °C as vehicles travelled for 45 min from farms to plants. Apparent equivalent temperatures of the monitored summer trips averaged 80.5 °C, indicating possible heat stress conditions based on the thermal comfort zones defined by literature index values. For longer trips, cooling assistance on the farms may be insufficient to prevent temperatures from rising further into extremely hot conditions in the transporters, leading to a dangerous thermal environment.

Abstract. Laboratory and farm-scale fluidized bed dryers are not available to purchase. Additionally, a deliberation is presently continuing regarding the beneficial and damaging effects of drying grain in a fluidized bed. Therefore, the goal of this research was to develop and test a custom-made small-scale fluidized bed dryer, suitable for moderate farms and capable of drying small and large size grains from high moisture content to a safe storage moisture content. The customary fluidized bed dryer was developed and constructed in the Rice Research and Extension Center, Stuttgart, Arkansas. The fluidized bed dryer was used to dry wheat from an initial moisture content of 23.3% db. The effects of the aspect ratio (bed height to bed diameter ratio) of 2, 3, and 4 m/m, the furnace temperature of no heat, 100°C, 150°C, and 200°C and drying duration of 10, 20, 30, 40, 50, and 60 min on the wheat moisture content, drying rate, and dryer efficiency were investigated. The lowest wheat moisture content of 16.3% db was observed at the lowest aspect ratio of 2 m/m, the highest furnace temperature of 200°C, and the longest drying duration of 60 min. Conversely, the highest wheat moisture content of 19.0% db was observed at the highest aspect ratio of 4 m/m, and the no heat condition. The drying rate of 0.47%/min was observed at the lowest aspect ratio of 2 m/m and the furnace temperature of 200°C after 10 min. The maximum dryer efficiency of 63.2% was achieved at the aspect ratio of 4 m/m, the furnace temperature of 200°C. Two empirical models were developed to predict the moisture content of wheat and the dryer efficiency as affected by the aspect ratio, the furnace temperature and the drying duration with the adjusted coefficient of determination of 0.91 and 0.88, respectively. Although, the developed fluidized bed dryer is a lab-scale system, the experimental results provided an exceptional indication to scale up the drying system to dry grains. Keywords: Dryer efficiency, Drying rate, Fluidized bed, Moisture content, Wheat-drying.

HighlightsMoisture sorption isotherms of rice and husk flour composites were determined.Adsorption isotherms were best modeled by the Chung-Pfost and Oswin equations.Desorption isotherms were best modeled by the Polynomial and Chung-Pfost equations.The Modified Oswin model was the best for both adsorption and desorption.Abstract. Empirical models describing isotherms specifically for adsorption and desorption have not been described for rough rice and husk flour composites. Such models are vital for process control and monitoring operations which use rice husk and rice flours or their mixtures for food or material processing. The current study was undertaken to determine the moisture sorption isotherms of rice husk flour, rough rice flour and their mixtures subjected to different temperature levels. Effects of rice husk flour to rough rice flour ratio of 0:1 (0.0%), 1:49 (2.0%), 1:16 (5.9%), and 1:0 g/g (100.0%) on rough rice moisture isotherms at temperature levels of 20°C, 40°C, and 60°C were investigated. The dynamic dewpoint isotherm technique (DDI) was used to generate accurate isotherms. Several empirical models were tested to fit the experimental EMC data. All the isotherms showed typical sigmoidal type 2 shapes. The equilibrium moisture content (EMC) over equilibrium relative humidity (water activity) ranging from 10% to 95% showed temperature dependence. Hysteresis was evident for all samples, with a decreasing level at a higher temperature. Rice husk flour to rough rice flour ratio, as a factor, showed a significant effect on the EMC of rough rice. The EMC decreased with an increase in rice husk flour levels. Chung-Pfost and Oswin were the two best models for describing adsorption isotherm, and Polynomial and Chung-Pfost were the best models for fitting the desorption isotherm. Modified Oswin model was the best model amongst the two-variable models for describing both adsorption and desorption isotherms. Keywords: Empirical models, Equilibrium moisture content, Rice husk flour, Rough rice flour, Sorption isotherms.

Abstract. Strategies for quantifying heat loss of broilers on live-haul trailers would be beneficial, particularly under conditions of environmental extremes. We have developed an electronic chicken (a self-contained, temperature-controlled heat source) to simulate the sensible heat loss of a live broiler during the transit and holding periods in commercial live-haul trips. The simulated electronic chicken is an aluminum box, having surface area equivalent to a 2.3 to 2.8 kg broiler chicken (0.13 m2), with a thermostatically controlled power source to maintain the internal temperature at 41°C (typical broiler core body temperature). Different cover materials were tested to identify an appropriate cover that resulted in measured values of electronic chicken heat production being similar to published values of sensible heat production for broilers. A double layer of fleece fabric provided a reasonable match. The sensible heat loss of the electronic chickens exhibited positive correlation with exposed wind, and a positive correlation with temperature gradient between internal and external environment. Wetting the fabric cover of electronic chickens only slightly increased heat loss as compared to the dry fabric cover. Wet fabric cover experienced lower heat loss than that expected from the wetted surface of a live chicken, therefore heat loss under the wet scenario would be underestimated. Electronic chickens were installed in modules on trailers with live chickens during commercial live-haul process under various environmental conditions and different management practices. Measured heat losses from electronic chickens were in the range of 8.2 to 20.3 W with outside temperature of -17°C to 3.0°C in winter, and 4.5 to 6.7 W with 28°C to 34°C in summer. Based on literature-reported sensible heat loss under thermoneutrality, it was determined that the measured air temperature inside the live-haul modules on the trailer in the range of 11°C to 25.1°C during transit (outdoor temperature range of 1.7°C to 22.2°C) and 5.3°C to 21.7°C during holding (outdoor temperature range of -9.1°C to 19.8°C) would allow the live chickens to regulate heat by their metabolism and stay comfortable. For the holding period, the winter trips were mostly in the zone of thermal comfort. In summers, hyperthermic conditions were possible during transit, although additional cooling due to surface wetting of birds as a result of misting (on the farm prior to beginning the transit) could have been beneficial but not detectable by electronic chickens. The electronic chickens can be used effectively as a model to evaluate and identify conditions that cause thermal stress conditions during live-haul conditions and to design systems and strategies to alleviate that stress. Keywords: Broiler transport, Physiological stress, Thermal micro-environment, Thermoneutral zone.